Heat-exchange apparatus



Jan. 20, 1931., PIJ. MCINTYRE .HEAT EXCHANGE APPARATUS Filed March 19, 192a Plasma a... 20, 1931 Eran stares arsasa'i Price PATRICK J. HOINTYRE, 0F IBETBOIT, MICHIGAN, WIGNOB TO WOLV'EBIN'E TUBE COM- ?ANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN HEAT-EXCHANGE AIBARATUS I Application filed March 18', 1928. Serial No. 262,921.

This invention relates to heat exchange apparatus and more particularly to an improved and simplified form of cooling or condenser coil. From the nature of the herein described apparatus it will be readily apparent that this apparatus is capable of many and valried uses. However,'it finds particular util-v connected by circularor round tubular sec:

tions at the ends thereof. With such a construction the fiat tubes constituting the fin receiving portions of the coil afiord. a greater radiating surface and provide an efiicient means for associating the fins therewith. By providing a coil, the bent portions of which areof circular cross section, in com bination with the flat coil sections, back pressure in the coil is eliminated or minimized by permitting a freedom of flow therethrough.

' Another object of the invention is to pro vide a construction of this character wherein each tube of the coil is rovided with separate fins and cooled ind pendently of the remaining tubes. 7

Still another object of this invention is to provide a construction of the herein described character which may be quickly and economically manufactured, assembled with facility and which will enjoy a'maximum efliciency.

The several objects, advantages and the novel details of construction of one embodiment of this invention will be mademore- .of a coil constructed in accordance with this invention.

v Figure 2 is'airagmjentary vertical sectional view taken substantially on the plane indicated by line 2-.2in Figure 1.

Figure 3, is a fragmentary longitudinal sectional view taken substantially on the plane indicated by line 33 in Figure 2.

Figure 4 is a fragmentary perspective" view of a section of the coil.

. Figure 5 is a detail sectional view taken substantially on the plane indicated by line 55 in Figure 1, and

1f igure 6 is a fragmentary elevational view of a length of tubing before the same is bent sections 10 are connected at the ends by curved or bent portions 11. Obviously by constructing the coil from a single length of tubing the necessit for jointafittin or other connections t erein s eliminate By reference to Figure 6 it will be noted that the coil is bent from a length of tubing 12 which has certain portions 13 thereof throughout its length flattened while the portions 14 intermediate the flattened 0rtions are left circular in cross section. e length of tubing which is to be bent to form the coil may be conveniently and economically prepared in this manner by taking a piece of tubing circular or round in cross section and flattening the tube at spaced straight parallel tubes 10 and the portions 14 which are circular in cross section form the bends or curved portions 11.

Numerous advantages are obtained such a construction. In the first place by forming the straight portions 10 of a flat tubular construction the radiating surfaces thereof are increased. In the second Fl the fin plates or members, yet to be re erre to, may be more conveniently associated therewith. In the third place, curved portions 11 of round cross section permit the contents of the coil to pass freely therethrough and prevent or e iminate to a large degree back pressure which might develop 'inthe coil. This back pressure results principally from the fact that the contents of the tube when flowing from one straight portion 10 to the next adjacent strai ht portion must reverse its direction of ow and if a tube of flat cross section-throughout its length were'bent to produce a coil of the herein described character the flow of the contents of the tube would be so restricted at the curved portions thereof as to produce considerable back pressure and thus reduce the efficiency of the device. Inwaccordance with the present invention the same advantages' are obtained as though a plurality of straight tubes were em loyed connected at iently developed from a flat sheet of metal Obviously the coils may which is bent to form a plurality of oppositely extending alternately arranged return-bent portions 16 and 17 respectively,

the crests of these return bent portions being arranged parallel or in the sameplane. The crest of each return bent portion 17 is formed with a depression 18 substantially corresponding in shape to one half of the cross sectional shape of the flat tube portions 10. A pair of fin members15 are associated with each of the tubes and the combined depressions 18 of each pair of fin members form recesses or I assages extending longitudinally or lengt wise of the fin members for accommodating the flat portions 10.

In assemblingthe fin members with the coil, solder is placed between those portions of'the fin members which engage the tube and also those portions of the fin members which engage one another. With the parts secured in this position the whole structure is subjected to a temperature sufiiciently to melt the solder and ,when the assembled structure is later removed and the solder permitted to hardenthe fin members are rlgidly secured to the tubes and to one another, an eflicient heat transferring union between the several members being provided. A layer of solder between the fin members 16 and the tube 10 is indicated by the reference character 19 and the line of solder between the engaging faces of the fin members is-indicated by the reference character 20.

, g be formed of any length or size and a heat exchange unit may e'me i w e i rie mb w soils associated with one another side by side in spaced parallel relation or in any desired or preferred manner. It is noted that a pair of fin 7 members is associated with each of the tubes 10, by this construction the mountin of the fin members upon the tubes isfacihtated and the effective heat radiating surface of the coil is increased.

While an embodiment of this invention has I been described and illustrated herein somewhat in detail it will be readily apparent to 7 those skilled in this art that various changesmay be resorted to without departing from the spirit and scope of this invention and to this end reservation is made to make such changes as may come within the purview of the accompanying claims.

What I claim as my invention is 1. In heat exchange apparatus, a single length of tubing bent to provide a plurality of-spaced straight parallel tubes and curved portions connecting the same, the straight tubes being of flattened cross section and the curved portions being of circular cross section. I

2. In heat exchange apparatus of the class described, a single form a plurality of straight spaced parallel tube sections and a pair of, fin members associated with each tube section, the pair of fin members associated with'each tube section being independent of the fin members associated with the other tube sections and each ength of tubing bent to fin member comprising a'strip bent to form a I plurality of oppositely extending alternately arranged return-bent portions, the opposed crests of the return-bent portions of said fin members being recessed for embracing engagement with said tube section and being secured to the corresponding portion of the other fin member of the same pair.

3. In the method of forming heat exchange coils, those steps which consist in deforming a length of tubing, at points throughout its length, to provide portions of flat tubular cross section and bending said length of tubing at the non-deformed portions to provide a plurality of straight tube sections.

4. In the method of formipg heat exchange apparatus, those steps which consist in deforming a length of tubing which is circular in cross sect-ion at spaced points throughout its length to produce portions of flat'tubularcross section and bending the tubes at the nondeformed portions thereof to provide a plurality of straight spaced parallel portions.

5. In the method of forming heat exchange apparatus, those steps'which consist in deforming a length of tubing which is circular in cross section at spaced points throughout its length to produce portions of flat tubular cross section and bending the tubes at the nondeformed portions thereof to provide'a lur t pf mishtpa e i r l r o and assembling fin members with the straight parallel portions.

6. In a heat exchange apparatus, the com bination of a plurality of spaced straight tube sections, each tube section being of flattoned cross sectional shape and being connected to the next adjacent straight tube section, and an independent set of fin members associated with eachstraight tube section.

7. The method of forming a heat exchange 

